The invention relates to an improved clamp for supporting a water-cooled induction coil for an induction heating machine, and which permits the coil to be easily removed from the machine and replaced by another water-cooled coil of the same or different size.
The clamp of the invention is of the same general type as the clamp fixture shown and described in U.S. Pat. No. 2,866,880 which issued Dec. 30, 1958, and which is assigned to the present assignee.
As described in U.S. Pat. No. 2,866,880, prior art induction heating machines are commonly provided with an output electrical terminal block for delivering high frequency electrical energy to the water-cooled induction heating coils associated with such machines. The patent describes an improved form of clamp fixture which is connected to the output terminal block of an induction heating machine and which serves removably to support the induction coil.
Induction heating coils used in the prior art induction heating machines are usually formed of metal tubing so that water or other coolant may be circulated through the coils. It is most important that water or other coolant be circulated through the coils whenever they are electrically energized in order to prevent overheating and resulting damage.
The clamp fixture described in U.S. Pat. No. 2,866,880 is constructed not only to support the induction heating coil in proper electrical contact with the electrical terminal block of an induction heating machine, but also to provide appropriate coupling to a coolant source for circulating a coolant through the coil.
The clamp fixture described in U.S. Pat. No. 2,866,880 includes in one embodiment manually operated valves in the coolant line to shut off the coolant whenever the coil is to be removed from the machine. A second embodiment of the clamp fixture described in the patent incorporates the coolant valve which is automatically turned off when the clamp is loosened to permit the coil to be removed. Also, when a new coil is inserted in the clamp and when the clamp is tightened, the coolant valve is automatically turned on in that particular embodiment. The mechanism of the second embodiment described in the patent assures that at no time will the coil be energized when no coolant is flowing through it. This provides a positive means to preclude severe damage which could result in destruction of the coil, and possible damage to the induction heating machine itself.
However, the second embodiment of the clamp fixture described in the patent is fairly complex, and an objective of the present invention is to provide a sturdy and simplified clamp assembly which achieves the desired results of the clamp fixture of the second embodiment of the patent by means of a simplified structure.